Typewriting machine



May 26, 1925.

F. A. HART TYPEWRITING MACHINE WITNESSES Q r IZNVENTEIRY v ww Hi5 ATTI'IR'NEY .Miy 26, 1925.

F. A. HAR I" TYPEWRITING MACHINE I Filed Opt. 5, 1923 s Sheets-Sheet z;

WITNESSES INVENTEIR HIE ATTORNEY To all whom it'may' concern:

Patented May 26, 19 25.

1,539,415 I D S ATES PATENT OFFICE.

FREDERICK A. HART, O]? NEW,BRITA.IN,

. CONNECTICUT, ASSIGNOB TO REMINGTON TYPE-WRITER .IGOMPANY, OF ILION', NEW YORK, ACOBPORATION OF. NEW YORK.

TYPEWRITING macnmn.

Application filed October 5, 19a. Serial in escape.

Be it known that I, FREDERICK A. HART, citizen of the United States, and resident of New Britain, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Typewriting Machines, of which the following is a specification;

.out in the claims.

My invention relates generally to paper feeding and controlling mechanism for typewriting machines, and its chief object is to provide new and improved mechanism of the character stated. More specifically the object of the invention is the provision of what is termed platen sweep mechanism-whichis particularly adapted for condensed record billing where there may be employed bill sheets having headings of different widths,

- varying from comparatively short headings to headings of great depth.

To the above and other ends'which-will hereinafter appear, my invention consists in inafter described and particularly pointed In carrying-out the preferred form of my invention, means are provided for continu-- ously turning the platen, or sweeping 1t as it is sometimes termed, to predetermined extents both forward and backward, devices being employed for limitingthe backward sweep to two less units of line'space distance than the forward sweep, in order that the condensed record shect remaining in the machine may be automatically positioned with- .out care on the part of the operator, for proper co-operation with each fresh bill sheet that is inserted and brought by the forward sweep of the platen into position for receiving the first line ofwriting undo the heading on the billsheet.

, My invention will be described in detailin relation to the accompanying drawings,"

' whereimj 1 Figure 1 is a fragmentary end view of the [carriage and platen-of a #11 Remington typewriting machine .e'mbodying my inven, tion.

Figures 2, 3' an'd 4 are diagrammatic end views partly in section illustrating difierent 7 in steps in the platen sweep operation. 7

"Figure 5 is a sectionalgview drawn to an enlarged scale, the plane of the-section beure 1 and looking in the-direction of the arrows at said line.

. Figure 6. is a perspective view illustrat- I 'ing different parts constituting a novel platen sweep mechanism, the parts being spread or separated for the sake of clearness.

The carriage of the #11 Remington ty ewriting mac iin'e comprises a truck and a platen frame, which latter is shif-tably mounted on the truck. For present purposes, however, applicant while employing the usual truck and platen frame, screws down the shift stops as is sometimes done,

so asto prevent the frame from shifting on the truck, and also employs at the right-hand end an additional bracket or en'd bar which issecured rigidly to the platen frame and is adapted to provide a support for certain novel parts hereinafter described. The. top plate 1 of the main frame of the machine supports front and rean guide rails, the rear rail 2-being shown herein. Said guide rails co-operate through arFifrictmn rollers '3 with the rooved rear b r 4 ofa rectangular truck. aid truck fu ther comprises end bars 5 which connect the rear bar 'witha rooved front bar. that also 00-.

similarly operates t rough antifriction rollers. with the front trackway, said trackwa however, together with the front bar and t eco-operating rollers being omitted from the drawing. The end bars 5 are formed with eye portions or perforated enlar ements 6 to afford passage-way for the p aten axles, and

threaded into the top and bottom of each enlargement is a stop screw 7 having acheck nut 8. The platen frame comprisesend bars 9 connected by. a transverse channel bar 10 underlying the platen and also by a cross rod 11, which cross rod connects the rear upper end'portions of the bars 9. Links 12 connect the end bars 9 with the truck. Supported; on the platenjrameand truck is a cylindrical platen 13 ro idedac its ri hthandend wlthaline spacing ratchet w eel 14 with which "co-operates the s" ring roller deten't 13.v The ,usual front an back feed rollers are conventionallyshown, and are "designated as 15." The left-hand mounting of t ,e platen is. of ordinary construction.

At itsiight-handeri'd a cover plate or head '16 is" amm ed outside the'rat-chet wheel 14 and is provided with alug 17 which engages a recess or notch 14" in theratchet wheel14 ing indicated by the section line 1-1 in Threaded into the; plate 16- is the left-hand end portion of an outwardly extending sleeve or tube 18. Slidably supported in the bore of the sleeve 18 is a stub shaft 19 provided at its outer end with the usual finger wheel 20, the inner end of said shaft being formed with a notch 21 which receives theflattened end portion or tongue 22 of a release rod 23 ada ted to release the clutch devices whereby 516 ratchet wheel- 14 is normally clutched to the platen, the unclutching o eration being effected by pushing in the nger wheel and causing the shaft 19 to force in the release rod 23. Ordinarily, when the finger wheel is turned the platen is turned also y reason of the co nnection.21', 22 between the rods 0r shafts 19 and 23. This construction also affords a ready detachment of the platen while leaving the stub shaft 19 in the platen frame. Step by step line spacing movements are communicated to the platen by the usual devices co-operating with the ratchet wheel 14, said devices as shown in Fig. 1 comprising a line spacing pawl 24, pivoted at 25 on a rotary carrier 26 mounted concentrically with the platen. Pivotally connected to the pawl 24 is the rear. end of a push link 24 which is connected by devices, not shown, with the usual line spacing handle mounted on the right-hand end bar 6 of the truck. The pawl 24 is normally disengaged from the ratchet wheel 14 but at each actuation of the line spacing handle or finger piece, said awl will be swung rearward to engagewlth the ratchet wheel, the pawl and carrier thereafter turning coaxially with the platen and effecting a unit of line spacing turninv movement of said platen.

When the platen is turned, the sleeve 18 turns in a tubular bearing member or sleeve 27 which is threaded through the right-hand end bar 9 of the platen frame. Sa1d sleeve 27' is formed at its left-hand end with a angular extension 32 whic tains the sleeve in rigid relationship with the end bar. The left-hand end of the flanged portion 28 of the sleeve is contiguous to the outer face of-the plate 16. Near its righthand end said sleeve 27 is additionally supported in an enlargement or hearing eye 30 forming the terminal portion-of an angular bracketor supporting member 31 which is arran ed parallel with the right-hand end bar 9 ut outside the truck andv is rigidly secured to said end bar. To secure or fix the bracket 31 to the end bar, said bracket at its upper rear end portion is rovided with an receives screws 33 that are threaded into the end bar 9. At its lower end, said bracket is provided with a boss or hub 34 which receives a long shoulder screw 35 that is threaded into the lower portion of theend bar- 9, a washer 36 being interposed between the inner end of the boss and the adjacent link 12. The'upper stop screw'7 is screwed down against the sleeve 27 and locked by its nut 8. Thus the sleeve is tightly engaged by the two opposing stop screws 7 so as to prevent shifting movements of the platen frame, the platen frame being thus held in rigid relationship with the truck, the stop screws at the opposite end of the platen frame being similarly set to prevent shifting movements. Of course, it is to be understood that the present invention is readily applicable to machines employing shifta 1e platens. It will further be understood that when the platen is turned by the line spacing devices, the sleeve 18 and the shaft or axle portion 19 will revolve together inside the stationary sleeve'or bearing 27.

In addition to the platen turnin or rotating devices comprisin the regu ar line spacing mechanism and t e finger wheel 20,

novel platen sweeping means are provided for continuously rotating the platen, or

sweeping it as is frequently termed, both forward and backward. Said means comprise generally a handle or crank arm which is concentric with the platen but normally disconnected therefrom and which controls pawl and ratchet devices for rotating'the platen in connection with novel stop devices for .variably limitin the extent of rotation both forward and ackward. Most of the devices comprised in the said means are mounted'on that portion-0f the sleeve 18 which extends outward -or rightward beyond the bracket 31. Sup orted loosely on said sleeve 18 adjacent to t e. outer or righthand face of the bracket 31 is a washer or spacing annulus 37. Contiguous to the washer 37 is a rotary stop member 38 comprising an annular portion 39 from which The latter comprises an annular portion 44' from which radiate spring fingers 45. These are adapted to bear against the left-hand face of a rotary cam member 46 having two circular faces ordwell portions 47 and 48 of different radii connected by a cam or incline 49, said member being provided with an .arm 50 having a notch indicated at 51 and being formed centrally with a hole 52 to fit over the sleeve 27.

Next succeeding the cam member on the sleeve is a wheel or disk 53 which combines the functions of a stop controller and pawl controller. Said periphery of the wheel 53 is smooth, the

wheel is formed centrally with a hole 54 to fit over the sleeve. The periphery of said wheel is formed with a series of square teeth 55 alternating with notches 56. Adjacent to the notched or toothed portion 55, 56, the

smooth surface however being interrupted by a slot or depression indicated at 57, the slot terminating in opposite parallel faces or walls 58 and 59. The outer .or right-hand face of the wheel or disk 53 is formed with a circular groove or depression 60 having a closed end6l, the opposite end running into an open mouth 62 having opposite faces or Walls 63 and 64. To the right of the notched wheel 53 is mounted a ratchet wheel-65 having preferably the same number of teeth as the line spacing ratchet wheel 14. The wheel 65 is provided with a rightwardly extending collar or hub portion 66 which is interiorly threaded and is also split at opposite sides as indicated at 67. The threaded hub '66 is screwed on the outer end of-the sleeve 18 which is exteriorly threaded at 27 to co-operate with the interior threads of the split hub 66. Mounted loosely on said hub contiguous to the ratchet wheel 65 is an arm 68 which is formed with a hole 69 to fit over the hub 66, said arm extending radially outward and carrying near its outer end a headed shoulder screw 70 which is secured in place by a check-nut 71 and provides a pivotal support for an adjustable stopmember 72 having a tooth 73 adapted to fit in the notches 56 of the wheel 53, said piv- ,oted stop 72, being provided with a flat vspring 74 which tends normally to maintain the tooth 73 locked or engaged in one of the notches, thereby locking the stop 72 to the.wheel 53. A handle or finger piece 75 projects outward from the stop 72 at one side of its pivot and may be manipulated to turn the stop 7 2 on said pivot to withdraw the tooth 73 from interlocking engagement,

freeing the stop 72 and the arm or carrier 68 so that they may be rotated tore-locate or re-adjust the stop. Mounted to bear loosely on th'ehub 66of the. ratchet wheel 65 is, a crank, sweep or rotary arm 76 pro vided with 'a laterally extending hub portion 77 bored out as indicated at 77F-to fit "over the hub 66. At its up erend' said tending 65 crank is rovided with a rig twardly exger piece or handle 78. Also mounted on the hub 66 to the" right of the crank is a securing device in the' form'offa collar 79 having a central'opening or hole 80 and a dividing cut or split 81, The split is bridged by a headed screw 82 which carries'on its projecting end a nut. 83. The

ment with thesleeve 27 By tightening the and clamp them firmly against the sleeve 27 so that when the ratchet wheel 65 is turned,

.Also the clamping device or collar 79 co operates with the spring spider 44, 45 to hold intervening parts frictionally and prevent rattle or undue movement. The crank 76 has pivoted to it at 84 a pawl arm 85 provided with a tooth 86 that is inthe plane of the ratchet wheel 65 but is normally separated 0r disconnected therefrom. The tail 87 of the pawl is adapted to co-operate with the lateral pin 88 on the crank 76. Near the free end of the pawl arm 85 is mounted a laterallyyprojecting pin 89 on which is pivoted a roller 90, sa1d roller being adapted to co-operate with the groove 60 in the wheel 53. The pawl arm or member 85 is loosely mounted on its pivot 84, movements of the pawl being positively controlled by the roller 90 in co-operation with the groove or trackway 60 and its mouth 62. Normally the pawl member is held as in Fig. 1, the roller 90 on aging in 'the mouth 62 and maintaining 12 e pawl tooth 86 up out of engage-- ment with the ratchet wheel .65, so that the platen may be turned either by the regular line spacing devices or by the finger wheels 20 independently of the pawl member 85 and the crank 76 and without disturbing the latter parts. The crank at this time remains 1n normal position, resting against the pin 42 of the stop member 38, which stopmember is temporarily fixed in a pre-determined normal position as hereinafter described. The pin 88 on the crank engages in the notch 51 in the cam member 46, thus positively connecting the cam member and the crank and forcing the cam member 46 to participate in all of the movements of the. crank.- The reduced end of the pin or connecting device 42 projecting rightward from the stop member 38 engages in the notch or wall 58, or 59 of the slot, the two parts are forced-to turn together by the connecting or engaging devices 42 and 57 and the arrestv art effects the arrest of the other; he stop member 38 is ada'pted to be arrested in both directions of its rotary of one part.

travel-by a projection or stop pin 91 which 1 is fixed to and projects rightward from the is arrested in the Fig. 1 position by co-operation of the rear edge of the arm 41 with the frame stop 91. In said Fig. 1 thedisk 53 -is also shown at the limit of its backward irotation by reason ofthe engagement of the bracket 31. Normally the stop member 38' wall 59 in the disk with the pin or stop 42 of the stop member. 'Withthe stop member in this position its pin is engaged by a locking device in the form of a Spring-mounted hook 92 pivoted on a pivot screw 93 that is thread-- ed into the bracket 31. Said'hook is constantly urged forward on its pivot by a wire spring 94 coiled around thescrew 93 between the bracket 31 and the inner face of the hook 92, the free end of the spring engaging with the back of the hook. Above its pivot the hook is off-set slightly towards the right so as to bring it in the same foreand-aft plane as the cam member 46, said hook being provided with a rounded projection or nose 92 which is contactive with the curved or arcuate dwells 47 and 48 and the cam 49. Through these faces or parts the cam member is adapted automatically to control the hook so as to throw it into and out of engagement with the pin 42. When the disengageable hook is engaged with the pin, the stop member 38 islocked or prevented from turning forward on its axis, the nose 92 at this time being engaged with the dwell 47 which is the curve of lesser radius.

Let it be assumed thatthe stop 72 be adjusted with its tooth 73 engaged, say, with a the ninth notch 56 of the wheelor disk 53 which is an adjustment of the stop that is suitable for a depth of heading equivalent to somewhat less than a complete revolution of the platen. With the partsas in Fig.1 it may further be assumed that a bill sheet has just been written and withdrawn, its entries having been duplicated on the underlying record sheet which remains in the machine. For the purpose of turning the platen 13 continuously backward and causing it through co-operation with the feed or pressure rollers 15 to retract the record sheet to a position where a fresh bill sheet may be" I introduced at the back of the machine in the Fig. 1 to the Fig. 2 position, the dwell.

; surface 47 riding under the, nose 92 without disturbing the hook 92 which remains engaged with the in 42 on the stop member 38 preventing orward movement of sa d stop member. The wheel ordisk 53, however, is free to turn and will be moved, as the result of friction primarily, to the Fig. 2 position, bringing the wall 58 of the slot 57 into contact with-the pin 42, thus temporarily arrestin the disk 53. It will be understood that t e disk as it turns carries with it the rotary carrier -68 and the stop? 2 interlocked with the disk in'predetermined position. During this movement, the relationship of the roller 90 with the mouth 62 of the groove 60 is not disturbed or altered, but when the disk 53 is temporarily arrested as described, the roller moving forward under the impulse of the crank will be pressed against the forward wall 63 of the positively maintained in engagement with the ratchet wheel by reason'of the co-operation of the roller 90 with the circular trackway 60. The crank is thus positively con- 'nected with the ratchet wheel which is rigidly related to-the platen, so that from this stage onward the impulse of the crank 7 6 is communicated to the platen, turning it as the crank .turns. It is to be understood, however, that during the initial stage of movement from the Fig. 1 to the Fig. 2 position while the disk 53 is turning relatively to the stop member 38, the platen will remain unafi'ected. This initial stage of movement of the crank without affecting the platen is equivalent to substantially two units of line space distance. The initial stage of movement from the Fig. 1 to the Fig. 2 position brings the cam face 49 into contact with the underside of the nose '92 so that a further pull communicated to the crank 76 from the handle 78' and thence transmitted through the crank pin 88 to the cam' member 46 will cause the cam face 49 acting against the nose 92 to force the hook 92 to turn rearward on its pivot 93 against the tension of its spring 94. This movement of the pawl automatically unlocks or frees the in 42 releasing the stop member 38. As the movement of the parts continues, the dwell face 48 will be brought into -co-operation with the nose 92*, the radius of this face being such that the hook 92 will be held back out of operative position during the remainder of the backward turning movement. The stop member 38 being now unlocked will be free to be turned by the disk or wheel 53, the wall 58 engaging with the pin 42 of the stop member and forcing it ahead. This movement of the parts will continue until the lug 40 of the stop member is brought intocontact with the under side of the frame stop or pin 91 as shown in Fig. 3. The stop member is thus positively arrested and its pin 42 being held against movement will consequently post tively arrest the disk 53. The adjustable stop. 7 2 is thus held against further turning movement being finally arrested in the Fig. 3 position. It will be observed from this figure that relatively unimportant changes in the relationship between the pawl 85 and the disk 53 and stop 72 take place in passing from the Figure 2 to the Figure 3 posiing of the crank 76 thereafter will force the pawl 85 ahead, causing its roller 90 to travel along the groove in the now motionless trackway 60 until the final arrest of the crank, pawl, and platen takes places, due to the contact of the front face of the pawl with the rear or contact face of the stop 72 as shown in Fig. 4.

As a result ,of this, backward turningmovement of the platen, the record sheet has been retracted to. a predetermined exthe described operations are reversed, the handle 78 and; the crank 76 be-ing pulledor turned forward. During the first stage of the return or forward movement all the parts will turn together without change in their relationship, after the lost motion between the wheel or disk '52} and the stop member 38 is taken up. In other words, the stop member initially will remain motionless until the wall 59 of the slot in the disk engages with the pin; 42 after which all the parts will turn togetheruntil the stop mem her is arrested by the arm ll engaging the stationary frame sto or pin 91. The arrest of'the sto mem er likewise results in the arrest of t e disk 53, and the parts are so timed that the cam face 49 of the cam 46 will run down overzthe nose 92 ermitting the hook 92 to re-engage with t e pin 42. The disk '53 having been arrested as described, the further turning of the crank" 7 6..

and the platen will" cause the roller 90 to move along through the grooved track-way 60 until said roller contacts with the rear wall 64 of the mouth 62, said wall acting as f a cam to lift the pawl 85 and disconnect its.

tooth 86 from the ratchet wheel 65. This disconnection however will not take place until after the pawl and ratchet have turned the platen on the'forward sweep through two more units of line space distance than 1t was turned during the backward sweep,

, this additional movement being due .tothe J the last line of the preceding bill sheet and the first line of the newly entered bill sheet."

fact that there is no lost motion of the pawl "relativeto the ratchet wheel, as there was.

at the beginning of the backward sweep. The result is that the record sheet will be advanced automatically to. space between By the described operations the new bill sheet has been advanced continuously .to apredetermined extent and brought into position to receive the first line of writing, while the underlying record sheet has likewise been, advanced and in position to re celve the next line of. writing, two units of line space distance nnderjthe' last preceding line of writin' Next,the operator actu. ates the usua printing,i instrunientalities (not shown) the imprints made on the bill sheet through the usual ribbon and.

being duplicated on the underlying record line spacing actuations, although of course -the ratchet wheel 65 will turn with the platen. The bill having been written or filled in is withdrawn and then the platen sweep mechanism is operated to'retract the record sheet to a predetermined extent after which a fresh bill sheet is inserted and "continuouslyadvanced along with the record sheet. in the described manner. The mechanism is rapid and efficient in operation and may be employed in the manner described to turn out in a comparatively short time a large number of typewritten bills, the entries bein duplicated on a record sheet or sheets an apart. I a Y i It will be understood that the extent of continuous turning movement communicated to the platen by'the crank before the arts are arrested by the stop devices may e varied in accordance with the depth of the heading on the bill sheet by adjustment .of the stop 72. The range of adjustment of the stop 1s of course determined by the se-. ries of teeth 55 in the disk 53, said disk being in effect a circular rack along which the stop 72 may be adjustably set. Said stop when in the uppermost notch 56in the disk viewed in the Fig. 1 position, is set to give the least extent of movement or sweep,.

nevertheless the employment of the mechanism is not restrictedto this particular use hut/it is also adapted to other styles of typewritten work in which continuous rotary, movements of the platen as distin-' guished Y from step-by-step line spacing movements are made use of.

What I claim as new'and desire to secure by Letters Patent is Y properly condensed or spaced I 1. In a typewriting machine, the coinbi- I nation of a laten, a fin or piece, operative connectlons. tween sai finger piece and said platen effective to, move saidplaten when saidfinger piece is actuated,= a stop 7 effective to limit the movement of said platen in one direction when actuated by said fin erpiece, locking devices for normally ,lockmg said stop against. movement, and devicesfor automatically rendering said locking devices 2. In a typewriting machine, the combination of a platen, a finger piece, operative connections between said finger iece and said platen eflective to move sa d platen when said fin er piece is actuated, a stop effective to limit the movement of said platen in one direction when actuated by said finger piece, and locking devices for normally locking said stop against movement, said finger piece being efi'ective to throw said locking devices out of use and to move said stop.

-3. In a ,typewriting machine, the combination of a rotary platen, a platen rotator provided with a finger piece, operative connections between said rotator and said platen,

.and a stop for positively limiting movement imiting movement of said platen by said rotator in one direction, a co-operative fixed stop, devices for locking said rotary stop normally against movement, and devices operative by said rotator to throw said looking devices out of use.

5. In a typewriting machine, the combination of a platen, a finger piece, operative connections between said finger said platen effective to move sa1d platen when said finger piece is actuated, and means for positively limiting the movements of said platen by said finger piece, said means comprising a rotary stop member, a cooperating frame-stop, a lock normally effect1ve on said rotary sto member, and devices actuatedbv said nger piece for controlling said loc 6. In a typewriting machine, the combination of a laten, a finger piece, operative connections tween said finger iece and said platen effective to move said platen when said finger piece is actuated, and means for positively limiting the movements of said platen. by said finger piece, said meanscomprising a rotary stop member, a co-operating frame-stop, a lock normally efi'ective on said rotary stop member,and a rotary cam member operative by said finger piece to throw out said lock. 1

7. In a typewriting machine, the combi-' nation of a laten, arfinger piece, operative connections etween sai finger .piece and said platen eflective to move saidplaten when said finger piece is actuated, and means for positively limiting. the movements of said'platen by saidfinger piece, saidmeans comprising a rotary stop, a co-operat'mg iece and frame stop, a spring pressed hook normally engaging said rotary stop to lock it against direction.

8. In platen sweep mechanism for typewriting machines, the combination of a re tary stop member having only a limited extent of rotary movement, a hook normally restralning said stop member from move- -ment, and a rotary member op'erative from the platen sweep handle and provided with twocircular dwell portions and an intervening cam portion, said portions being cooperative with said hook.

9. In a typewriting machine, the combination of a platen, a finger piece, operative connections between said finger piece and said laten, a rotary stop provided with a plura ity of fixed projections, a frame stop co-operative with said projections to limit turning movements of saidrotary stop, and a normally efiective lock for said rotary stop.

In platen sweep mechanism for ty ewriting machines, stop devices for limiting continuousrotary movements of the platen, said devices comprising a pair of rotary stop members having a permanent lost motion connection.

11. In platen sweep mechanism for typewriting machines, stop devices for limiting continuous rotary movements of the platen, said devices comprising a pair of rotary stop members. and a pin and slot connection between said stop members permitting their limited relative movement.

12. In platen sweep mechanism for typewriting machines, stop devicesfor adjustably limiting continuous rotary movements of the platen, said devices comprising a pan of rotary stop members permanently connected together but capableof limited relative movement, and a stop adjustable on one of said stop members.

13. In 'pla-ten sweep mechanism for typewrit-ingmachines, the combination with a platen and a platen sweep, of stop devices for limiting continuous rotary movements of the platen, said devices comprising a pair of rotary stop members ermanently connected together but capab e of limited relative movement, one of said stop members heing formed with peripherahteeth, a'sto carrier, at stop pivoted: on said carrier an adjustable. to' engage with pie-determined ones of said-teeth, and a second stop on the platen sweep itself co-operative with said adjustable stop, I 14. In a typewritmg machine, the combination with a platen and a platen, sweep,

of stop devices limiting continuous rotary movements of the platen, said devices comprising a pair of rotary stop members havin a permanent lost motion connection, a pair of stops on one of said stop members, said pair having an unvarying relationship, a frame stop cooperative with said pair of stops, and a stop adjustable on the other of said stop members.

15. In a typewriting machine, the combination with a platen and a platen sweep, of devices for limiting continuous rotary movements of the platen, said devices comprising two rotary stop members, and means 20. In a typewriting machine, the combinormally'preventing movement of one of said members, said means normally affording restricted rotary movements qt the other stop member.

16. In platen sweep mechanism for typewriting machines, the combination of stop devices for limiting continuous rotary movementsof the platen, said devices comprising two rotary stop members, a hook normally engaging one only of said stop members, and connecting devices on the stop members co-operating to afford limited movement of the disengaged stop member.

17 In platen sweep mechanism for typewriting machines, the combination of stop devices for limiting continuous rotary move-.

ments of the platen, said devices comprising two rotary stop members, a hook normally engaging one only of said stop members, connecting devices on the stop members co-operating to aiford limited movement of the disengagedstop member, and

ineansacting automatically on said hook to release both of said stop members.

18. In a typewriting machine, the combination with platen and a platen sweep, of stop devices for limiting continuous rotary movements of the platen, said devices comprising two rotary stop members, a in on one of said stop members constant y en gaging a slot in the other of said stop members, and a disengageable hook normally engaging said pin. 19. In a typewriting machine, the combination with a platen and a platen sweep, of stop devices for limiting continuous rotary movements of the platen,'said devices comprising two rotary stop members, a pinch one of said stop member's constantly engaging a slot in the other of said stop members,

a disengage-able hook' normally I engaging said pin, and means for; disengaging said hook from said pin.

nation with a platenand a platen sweep, of stop devices for limiting continuous rotary movements of the platen, said devices comprisin two rotary stop members, a pin on one 0 said stop members constantly engaging a slot in the other of said stop members, a disengageable hook normallyfengaging said pin, and a rotary cam operative from the sweep handle to release said hook from said pin. p

21. In a typewriting machine, the combination with a platen and a. platen sweep, of stop devices for limiting continuous ro tary movements-of the platen, said devices comprising two rotary stop members, a pin on one of said stop members constantly engaging'a slot in the other of said stop members, adisengageable hook normally engaging said pin, a spring for said hook, a rotary cam operative from the sweep handle to release said ho'ok'from said pin, a'rotary member interposed between said stop members and controlled from the platen sweep said pawl is pivoted, devices for limiting continuous rotary or sweeping movement of the platen under the impulse of sa1d pawl and ratchet, saiddevices-comprisinga pair.

of rotary stop members having a permanent v lost motion connection, and means on one of said stop members co-operating with said pawl to maintain it positively engaged with the ratchet .Wheel as the platen is continuously rotated.

23: In a typewriting machine, the combination of a rotary platen, a ratchet wheel connected to the platen, a normally disengaged pawl co-operative with the ratchet wheel, a. rotary platen sweep arm on which said pawl is .pivoted, devices for limiting continuous rotary movement of the platen under the impulse of said pawl and ratchet, said devices comprising a pair of rotary stop members, a pin and slot connection between said stop members permitting limit- 'ed relative movements thereof, a circular trackway in one of said stop members, and a pin on said awl engageable with said trackway to maintain positive engagement between said pawl and said ratchet wheel during continuous back and forth rotary sweeping movements of said platen.

24:. In a typewriting machine, the combination of a rotary platen, a ratchet wheel connected to the platen, a normally disengaged pawl co-operative with the ratchet wheel, a rota crank having a finger piece and arm on w ich said pawl is pivoted, de

.vices for limiting continuous rotary movementof the platen underthe impulse'of said pawl and ratchet,-said devices comprising a air. of rotary stop members permanent y connected together but capable of member, a cam operative by said rotary limiting rotary movement, one of said stop members being formed with peripheral teeth, an adjustable stop co-operative with said teeth, a circular groove in said toothed stop member, and a pin carried by said pawl engageable with said groove.

25. In a typewriting machine, the combination of a rotary platen, a ratchet wheel connected to the platen, a normally disengaged pawl co-operative with the ratchetwheel, a rotary hand operated sweep on which said pawl is pivoted, devices for limiting continuous rotary movement of the platen under the impulseof said pawl and ratchet, said devices -comprising'two' stop members, a hook normally engaging one only of said stop members, devices on the stop members co-operating toafiord limited relative movementof the stop members, a circular groove-in said disengaged stop sweep to disengage said hook, and a pin on said pawl co-operative wlth said groove.

26. In a typewriting machine, the combination of a platen frame, a platen provided with a stub shaft projecting from its "end, and a second stub shaft disconnectibly connected with the first stub shaft and provided with a platen finger wheel operative to move both of said shafts.

27. In a typewritin machine, the combination of a platen rame, aplaten provided with an outwardly extending stub October, A. D. 1923.

. FREDERICK A. HART.

Witnesses:

CHARLES E. SMITH, LILLIAN NELSON. 

